The engine of SEM659 loader adopts Shangchai C6121 engine, large displacement, the unique design of intake system, large reserves of torque, strong power, quick reaction, which particularly are used for heavy work. Structure design adopts FEA finite element analysis, fixed shaft gearbox which is made in Germany's ZF, power shift transmission, shift light and flexible, high reliability and long life. The kick-down switch to improve operating efficiency. The drive axles of large module gears have good durability and designed for heavy industry status. The improved cab and engine hood expand driver horizons much more and greatly enhance the anti-damping effect of the cab. It compromises the international advanced materials technology cooling system To ensure that machines in the 40-degree heat and high dust environment to continue to work with high-performance; Re- optimized to match the engine's power to improve the efficiency of the whole operation and performance; The design and manufacture of hydraulic valves adopt the international advanced technology, According to DIN, SAE standards, fluid pressure hose have some features of good quality, reliability and improving performance of hydraulic system.